A teenage waitress overdosed on caffeine after drinking 14 shots of espresso.
Jasmine Willis, 17, could hardly breathe and was taken to hospital with a high temperature and heart palpitations.
She had drunk almost three times the recommended daily amount of caffeine in just four hours.
The Department of Health advises people not to drink more than five single espressos or four cups of instant coffee a day.
Earlier this year scientists questioned the validity of the traditional view that caffeine can reduce the effects of tiredness and increase alertness.
Coffee has been found to have some health benefits, however, Studies have suggested it can protect against the onset of Parkinson's disease and keep the mind sharp into old age.
Tea and coffee also contain a wealth of other health-boosting compounds.
A spokesman for the British Coffee Association said: "There are thousands of published studies which demonstrate clearly that moderate coffee drinking - four to five cups a day - is perfectly safe.
"Increasingly, there is evidence to suggest that there are health benefits from it. The key to any healthy, balanced diet is moderation in all things and this applies to coffee."